This invention concerns an adjusting apparatus for one or more reflectors of a motor vehicle headlight with which a reflector, which is enclosed in an interior of a headlight housing by a light-transmissive shield, can be pivoted about an axis, there being two angled transmission units coupled to one another in the interior of the housing, the first angled transmission unit comprising a first miter gear mechanism having a toothed-gear pair with a pin toothed-gear thereof being coupled to, and rotatable with, an adjusting pin which couples the reflector with a rearward housing wall, and with a shaft toothed-gear thereof being positioned between the pin toothed-gear and a bearing box of the rearward housing wall, and a second angled transmission unit, at a remote end of the first miter gear mechanism, being rotatably mounted in an opening of the housing and having a rotatable knob thereon, manipulatable from an exterior of the housing.
Such an adjusting apparatus for a motor vehicle headlight reflector is disclosed in German patent DE 35 25 618 A 1. The angled transmission unit which is coupled to the first miter gear mechanism has a flexible shaft which is shoved onto an irregularly-cross-sectioned pin at the first miter gear mechanism and is thereby rotatable coupled with a shaft toothed-gear whose teeth interengage with teeth of a pin toothed-gear of an adjusting pin, and which, with the adjusting pin, is held radially and axially in a bearing box of a housing rearward wall by a cover which serves as an attachment device. In this regard, the adjusting pin extends through an opening in the cover and an end portion thereof which extends toward the rearward housing wall engages with a shell-like rim formed on the housing wall. A bearing in the housing rearward wall for the shaft toothed-gear of the first miter gear mechanism, which is coupled to the flexible shaft to be rotatable therewith, is a peripheral ring groove in the housing wall and the cover in which a ring collar of each of the shaft toothed-gear and the adjacent flexible shaft respectively engage. With such a bearing arrangement for the flexible shaft, and with the toothed-gear's coupling therewith to be rotatable therewith, the ring collars of the flexible shaft and the shaft toothed-gear, and the ring groove for receiving them, must be dimensioned so as to exactly fit together so that the ring collar of the flexible shaft is not restricted from movement by too little play nor that the shaft toothed-gear, which is coupled to it, is allowed too great a position deviation to the adjacent pin toothed-gear with too much play. Upon mounting the cover, which covers both of the toothed-gears of the first miter gear mechanism, one must be particularly careful that the portion of the ring groove formed by the cover and the portion of the ring groove formed by the housing fit exactly together. The rotation axis of the shaft tooth gear of the first miter gear mechanism with which the flexible shaft is coupled for rotation, extends horizontally and almost parallel to the rearward housing wall while the rotation axis of a rotation knob mechanism, which is rotatably mounted in an opening of the housing, extends almost parallel to the adjusting pin of the first miter gear mechanism. The flexible shaft defines, between the knob mechanism and the first miter gear mechanism, a large bow so that there is no danger of the flexible shaft becoming kinked. However, because of this the flexible shaft extends quite far into the interior of the housing and can, therefore, only be used with a particular space availability in the interior of the headlight. The flexible shaft is shoved onto an irregularly-shaped end portion of a pin at the knob mechanism whose other end supports the knob and which is rotatably mounted in an opening of the housing between both end portions. Mounting the flexible shaft is inconvenient during mass production and is time consuming, and further the flexible shaft is cost intensive to manufacture and its attachment with the pin carrying the knob, relative to a release thereof, is not certain. Upon adjusting the reflector via both of the angled transmission units it is further disadvantageous that, because of the flexibility of the shaft, a hysteresis is created by means of which the reflector could be jerked to a misadjustment. Jerked misadjustments lead to, during mass production, in inexact adjustment of the reflector.
It is an object of this invention to provide an adjusting apparatus for one or more headlight reflectors of the type described in the opening paragraph above in which the first and second angled transmission units, which are coupled to one another, extend into an interior of a housing as little as possible and which comprises as few parts as possible which are as easy to mount as possible. Further, it is an object of this invention to provide such an adjusting apparatus in which both angled transmission units can be cost effectively manufactured and function extremely reliably.